Roller-bearing caster.



No; 000,500. PATENTED 000. 20, 1905. P. R. WOLPINGER.

ROLLER BEARING GASTBR. APPLICATION FILED MAY 24, 1904 RENEWED JUNE 10.1905.

llllh I UNITED STATES PATENT UFFIGE.

Specification of Letters Patent.

Patented Dec. 26, 1905.

Application filed May 24, 1904. Renewed June 10, 1905- Seria1N0f264H736.

To all whom, it may concern:

Beitknown that I, FRANCIS R. WOLFINGER,

. a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Roller- Bearing Casters, of which the following is 'a specification.

This invention relates to casters, the object of the invention being toprovide a simple, cheap, reliable, and effective ball-bearing caster in which provision is made for reducing the strain on the caster to a minimum,

and thereby imparting durability to the same.

It is also an object of this invention to construct the parts of the caster in such a manner as to reduce friction to a minimum,while placing the weight of the furniture directly on and over the centers of the balls.

With the above and other objects in view,

' the nature of which will more fully appear as the description proceeds, the invention consists in the novel construction, combination, and arrangement of parts, as hereinafter fully described, illustrated, and claimed.

In the accompanying drawings, Figure 1 is a side elevation of the caster embodying the present invention. Fig. 2 is a vertical longitudinal section of the same. Fig. 3 is also a vertical section taken at right angles to Fig. 2. Fig. 4 is a plan view of the notched disk or securing-plate. Fig. 5 is a plan view of the connected friction-balls and the retainersleeve.

Like reference-numerals designate corresponding parts in all figures of the drawings.

The caster contemplated in this invention comprises, essentially, a horn or frame 1, embodying pendent ears or lugs 2, connected at their upper ends by means of a perfectly-flat and horizontally-disposed top or cap 3,while the ears or lugs 2 are connected at their lower ends by means of a shaft 4, upon which is. journaled a caster-wheel 5, the latter being preferably provided with steel or brass bushings 6 for imparting increased durability and wearing qualities to the caster.

The flat top or cap 3 is provided with a central opening for the reception of a bolt, pin, or screw 7, provided at its lower end with an enlarged head 8, which lies beneath the top or cap 3, and a smooth portion 9, which extends upward through the opening in the cap and also through the tubular boss 10 of an attaching plate or disk 11. The

disk 11 is secured to the shank of the screw 7 by means of a pin or key 12, so that the screw and plate are prevented from relative rotation. The plate is peripherally notched, as shown at 13, to facilitate turning the part 7 and fastening the caster as a whole to a piece of furniture, the notches 13 being further adapted to receive screws or other fasteners driven into the furniture for the purpose of securing the disk or plate 11 thereto and preventing rotation of said plate or screw 7. Sufficient space is left between the disk 11 and the top or cap 3 to admit of the introduction of a circular series of antifriction-balls 13 which surround the smooth shank 9 of the screw. 5

Just above the balls 13 is a loose bearing plate or disk 15, which surrounds the screw and has connected therewith in any suitable manneras, for instance, by forming them integral with each other-a retainer ring or sleeve 14, which holds the balls in place. It will be observed that the plate serves to hold the retainer-ring elevated a slight distance above the flat top or cap 3, so as to provide an eXitopening for dirt.

By means of construction above described the upperportion'of the caster-frame and bearings are relieved from twisting strain, the balls carrying the entire load, and thus reducing the friction to the minimum. The balls move in contact with perfectly-flat surfaces instead of the usual grooves or ballraces, and this also has the effect of reducing friction, the balls playing loosely around the smooth shank of the part 7 and within the retainer-sleeve. The construction described also enables the caster-wheel to be brought almost directly under the actual center of the bearing around which the caster as a whole turns.

Having thus described the invention, what is claimed as new is 1. A ball bearing caster comprising a frame provided with a flat top or cap, a shank passing upward through the cap and having a smooth portion, an attaching-plate surrounding and secured to the shank, antifriction-balls surrounding the shank, and bearing against the smooth portion thereof an upper bearing-plate between the balls and the attaching-plate, and a retainer-sleeve connected with the bearing-plate and being thereby held away from the fiat top or cap.

2. A ball bearing caster comprising a frame, a shank passing upward therethrough and provided with a smooth portion, a peripherally-notched disk surrounding and fastened to the shank, antifriction-balls interposed between the flat top of the frame and the attaching-plate, a loose retainer-sleeve surrounding the balls, and an upperbearingplate to which the retainer-sleeve is connected and by means of which said sleeve is supported away from the flat top. 10 In testimony whereof I a'HiX my signature in presence of two witnesses.

FRANCIS R. WOLFINGER. Witnesses:

CLARENCE I. WOLFINGER, G. RAYMOND CoLLINs. 

